Related papers: CP-violation in Compton scattering
The spin-independent part of the virtual Compton scattering (VCS) amplitude from the nucleon is calculated within the framework of heavy baryon chiral perturbation theory (HBChPT). The calculation is performed to third order in external…
A key question in understanding the structure of nucleons involves the role of sea quarks in their ground state electromagnetic properties such as charge and magnetism. Parity-violating electron scattering, when combined with determination…
An analytic calculation of the differential cross section for elastic Compton scattering on the deuteron at photon energies \omega in the range of 25-50 MeV is presented to next-to-next-to-leading order, i.e. to an accuracy of \sim 3%. The…
During the workshop "Compton Scattering off Protons and Light Nuclei: pinning down the nucleon polarisabilities" (ECT*, Trento, Italy, 29 July -- 2 August 2013, http://www.ectstar.eu/node/98), recent developments had been reviewed in…
We analyze the CP-violating electric dipole form factor of the nucleon in the framework of covariant baryon chiral perturbation theory. We give a new upper bound on the vacuum angle, |\theta_0| \lesssim 2.5 \cdot 10^{-10}. The quark mass…
We review the current state of knowledge of the nucleon polarizabilities and of their role in nucleon Compton scattering and in hydrogen spectrum. We discuss the basic concepts, the recent lattice QCD calculations and advances in chiral…
We investigate possible CP violating effects in $e^+e^-$ annihilation into top quark pairs. One of the interesting observable effects is the difference in production rates between the two CP conjugate polarized states $t_L\bar t_L$ and…
We summarize our paper hep-ph/9908390, where we find that in some regions of supersymmetric parameter space, CP violating effects that mix the CP-even and CP-odd Higgs bosons can enhance the neutralino annihilation rate by factors of 10^6,…
In top-pair events where at least one of the tops decays semi-leptonically, the identification of the lepton charge allows to tag not only the top charge but also that of the subsequent b quark. In cases where the b also decays…
For the neutron to have an electric dipole moment (EDM), the theory of nature must have T, or equivalently CP, violation. Neutron EDM is a very good probe of novel CP violation in beyond the standard model physics. To leverage the…
We examine how large violation of CP and T is allowed in long base line neutrino experiments. When we attribute only the atmospheric neutrino anomaly to neutrino oscillation we may have large CP violation effect. When we attribute both the…
We present fixed-$t$ subtracted dispersion relations for Compton scattering off the nucleon at energies $E_\gamma \leq$ 500 MeV, as a formalism to extract the nucleon polarizabilities with a minimum of model dependence. The subtracted…
We identify new room for CP violation in lepton flavor violating observables not bound by the electric dipole moment of leptons. By focusing on new physics in the muon-electron sector, we show that CP violation can make its first appearance…
If new CP violating physics contributes to neutral meson mixing, but its contribution to CP violation in decay amplitudes is negligible, then there is a model independent relation between four (generally independent) observables related to…
Measuring Compton scattered photons and recoil neutrons in coincidence, quasi-free Compton scattering by the neutron has been investigated at MAMI (Mainz) at $theta^{lab}_\gamma=136^o$ in an energy range from 200 to 400 MeV. From the data a…
We investigate the dependence of polarisation observables in elastic deuteron Compton scattering below the pion production threshold on the spin-independent and spin-dependent iso-scalar dipole polarisabilities of the nucleon. The…
Charge symmetry breaking contributions to the proton's neutral weak form factors must be understood in order for future measurements of parity violating electron-proton scattering to be definitively interpreted as evidence of proton…
Compton scattering provides important insight into the structure of the nucleon. For photons up to about 300 MeV, it is parameterised by six dynamical dipole polarisabilities which characterise the response of the nucleon to a monochromatic…
In supersymmetric theories the charged sleptons of different generations may oscillate amongst themselves while they decay. In the case of three generation oscillations, superpartner production at the LHC and NLC may lead to an observable…
We present an analysis of $13$ observables in Compton scattering on the proton. Cross sections, asymmetries with polarised beam and/or targets, and polarisation-transfer observables are investigated for energies up to the $\Delta(1232)$…